Bernie Sanders and Hillary Clinton shake hands at the end of the Democratic presidential debate hosted by ABC News at Saint Anselm College in Manchester, New Hampshire, on December 19, 2015.
JEWEL SAMAD/AFP/Getty
Bernie Sanders and Hillary Clinton shake hands at the end of the Democratic presidential debate hosted by ABC News at Saint Anselm College in Manchester, New Hampshire, on December 19, 2015.
Now playing
02:13
Hillary Clinton turns up the attacks on Bernie Sanders
CBS
Now playing
01:43
Hillary Clinton defends Bill not resigning
CNN
Now playing
02:12
Clinton: Kavanaugh ceremony a political rally
Now playing
01:48
Clinton laughs at Kavanaugh's comment
CBS
Now playing
01:00
Hillary Clinton makes cameo on 'Murphy Brown'
hillary clinton amanpour impeachment_00014522.jpg
hillary clinton amanpour impeachment_00014522.jpg
Now playing
01:47
Clinton: Impeachment 'will be left to others to decide'
hillary clinton republicans amanpour intv vpx_00000000.jpg
hillary clinton republicans amanpour intv vpx_00000000.jpg
Now playing
03:04
Clinton: Civility starts by electing Democrats
Now playing
00:55
Clinton ends Franklin tribute with smartphone
CNN
Now playing
01:49
Clinton rejects Trump comparisons to her husband
Schomburg Center
Now playing
01:58
Bill Clinton: I apologized for Lewinsky scandal
US President Donald Trump (L) and Russian President Vladimir Putin arrive for a meeting in Helsinki, on July 16, 2018. (Photo by Brendan Smialowski / AFP)        (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images)
BRENDAN SMIALOWSKI/AFP/Getty Images
US President Donald Trump (L) and Russian President Vladimir Putin arrive for a meeting in Helsinki, on July 16, 2018. (Photo by Brendan Smialowski / AFP) (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images)
Now playing
04:21
Fact check: Hillary Clinton's misleading comments
Former US Secretary of State Hillary Clinton speaks at the Eighth Annual Women in the World Summit at Lincoln Center for the Performing Arts on April 6, 2017, in New York City.
Angela Weiss/AFP/Getty Images
Former US Secretary of State Hillary Clinton speaks at the Eighth Annual Women in the World Summit at Lincoln Center for the Performing Arts on April 6, 2017, in New York City.
Now playing
00:39
Hillary Clinton goes after al-Assad, Putin
AUSTIN, TX - NOVEMBER 17:  Former U.S. Secretary of State Hillary Rodham Clinton signs copies of her new book 'What Happened' at BookPeople on November 17, 2017 in Austin, Texas.  (Photo by Rick Kern/WireImage)
Rick Kern/WireImage/WireImage
AUSTIN, TX - NOVEMBER 17: Former U.S. Secretary of State Hillary Rodham Clinton signs copies of her new book 'What Happened' at BookPeople on November 17, 2017 in Austin, Texas. (Photo by Rick Kern/WireImage)
Now playing
01:29
Clinton: Trump parrots what Putin says
TV3
Now playing
01:01
Clinton: Children treated as political pawns
Broadway Video/Universal Television
Now playing
01:15
Miley Cyrus tears up thanking Hillary Clinton
RBG on sexism and HRC_00010727.jpg
RBG on sexism and HRC_00010727.jpg
Now playing
01:50
RBG says Clinton was criticized worse than men

Story highlights

Clinton is leading Sanders 42% to 40%

Uncommitted voters make up 14% of the caucusgoers, according to the poll

Washington CNN —  

Hillary Clinton’s edge over Bernie Sanders has shrunk to just two percentage points in Iowa, according to new Bloomberg/Des Moines Register poll of likely Democratic Iowa caucus voters released Thursday.

Clinton tops Sanders 42% to 40%. Ex-Maryland Gov. Martin O’Malley was at 4% in the new poll.

Last month, a Bloomberg/Des Moines Register poll found Clinton was ahead of Sanders by 9 points, 48% to 39%.

In the new poll Thursday, 14% of those surveyed say they are uncommitted. In December, 8% were uncommitted.

Support for the candidates mirrors that in other polls. Sanders is strongest among younger voters, while Clinton is leading with older voters and women.

In a contrast between Republicans and Democrats, 57% of Democrats say the election is more about issues than leadership, 52% of Republicans say the election is more about leadership than issues. The Des Moines Register/Bloomberg had released a poll of likely GOP caucus-goers on Wednesday.

The poll was conducted from January 7 to 10 for Bloomberg Politics and the Des Moines Register by Selzer & Co. The poll included 503 likely Democratic caucus-goers and has a margin of error of plus or minus 4.4 percentage points.